The present inventions relate to engineering devices designed for generating gas-droplet streams, which can be essentially used in fire fighting facilities to produce fog-type screens and directed fire extinguishing two-phase flows. Thereto, the inventions can be employed in farmingxe2x80x94for field sprinkle and different substance dispersion, as well as at home, e.g., for disinfecting substance dispersion in the rooms.
Known in the art are different types of devices for gas-droplet stream generation. Thus, e.g., the prior art device for liquid dispersion is known described in Application RU 94003528 A1, which includes a gas-dynamic nozzle connected with a toroidal vortex chamber, a water supply system connected with the chamber via injection channels, and an air supply system connected with the nozzle inlet.
During the operation of the said device the liquid is supplied through the injection channels into a toroidal vortex chamber in the form of thin streams. While outflowing through the nozzle, on account of pressure difference occurred in the vortex chamber, the liquid streams are caught by a gas flow and begin to crush into fine drops. With gas flow and liquid drop acceleration the further drop crushing takes place in the divergent part of the nozzle and an accelerated gas-droplet stream is produced at the nozzle exit. The number of injection orifices and their diameter allow to change the number and diameter of liquid streams in the vortex chamber, which finally effects the droplet diameter in a gas-droplet stream.
However, the said device does not allow independently to control liquid and gas supply to the mixing chamber during the operation. Besides, in the said device a gas-and-liquid flow acceleration is possible only in the divergent part of the nozzle, which excludes a possibility of using a nozzle in the form of a converging tube.
The mostly closely analogous device of the one claimed is the prior art device for generating a gas-droplet stream described in Application WO 98/01231 A1, which contains a gas-dynamic nozzle connected with a liquid and gas mixing chamber, a means of liquid flow dispersion supplied to a mixing chamber with injection orifices, and a liquid and gas supply system.
The mixing chamber location in front of the nozzle inlet allows to use changeable gas-dynamic nozzles of different configuration and size. To produce an accelerated air flow supplied to the mixing chamber the said device employs a turbocompressor unit as a part of a gas supply system. The structural embodiment, though allowing to control a gas flow and pressure, does not provide individual control of gas and liquid supply to the mixing chamber, which is necessary for the device operation with minimum working fluid losses and required fast operation in an impulse mode.
Known in the art are also the valves for two-phase working fluid supply, with the help of which one can control different component supply sequence forming a two-phase flow of a working fluid in the mixing chamber (see description of Patents RU 2067712).
The prior art valves include the supply chamber of different components divided by a movable partition sealed along the valve body by a sealing ring or a membrane, a closure member, a seat, and a control valve. The dividing partition has a ring band between a seat and a closure member. With a control signal entering the drive a control valve opens one channel and closes the other channel. As a result of this there occur a connection of a closure member control chamber with the mixing chamber and a closure member displacement on account of pressure drop in the chamber. Following the closure member opening there takes place a dividing partition displacement opening an annular channel, through which the second component enters the mixing chamber. With a control valve closure there, first of all, takes place a shut-down of the first component passage channel by the closure member and then comes a shut-down of the second component passage channel by a diving partition.
Therefore, in the said valve-mixer only a certain sequence of supply and supply cutoff of different components to the mixing chamber may be carried out, which does not meet a gas and liquid mixing chamber supply sequence required for generating a gas-droplet stream. Besides, a particular arrangement of valve units and its size do not allow to use any other means for liquid flow dispersion supplied to the mixing chamber.
The most closest analogous device of the valve claimed is the prior art three-way valve for a two-phase working fluid known from the Author""s Certificate SU 327355 A, which has two closure members located on the rod and interacting with the seats, a rod displacement limiter, and a rod displacement control system. The valve seats are on the walls of the sealed chambers connected, accordingly, with liquid and gas supply pipes.
When the pressure drops in the gas chamber of the said valve there occurs a displacement up to a stop of a spring-controlled seat together with a closure member mounted on the rod. The second closure member also mounted on the rod, while displacing together with it, opens a liquid supply channel to the subvalve space. When the pressure rises, the displacement opposite to what has been described above and the gas supply channel opening to the subvalve space tale place.
This technical solution is aimed at excluding the working fluid mixing at the valve exit. On account of this the selection of liquid or gaseous phase from the vessel is carried out depending on its pressure.
Regardless of structural similarity a technical problem solved by the said valve is opposite to that one, at the solution of which the present invention is aimed, namely, control of gas and liquid flow mixing supplied to the mixing chamber in the form of a specific size droplet.
A group of present inventions patented are based on the problem of increasing the speed of attaining a required gas-droplet stream generation mode under continuous and impulse starts, as well as reducing the working fluid nonproductive losses under the device multistarts. The solution of this problem, in its turn, is based on ensuring a possibility to control a liquid and gas supply to generate a two-phase flow in the mixing chamber, which is then accelerated in the nozzle with a gas-droplet stream formed.
The solution of these problems is aimed, on the whole, at increasing gas-droplet stream generation efficiency and its performance stability.
This technical result is achieved by the fact that in the device for generating a gas-droplet stream comprising a gas-dynamic nozzle connected with a liquid and gas mixing chamber, a means of liquid flow dispersion supplied to the mixing chamber with injection orifices, and a liquid and gas supply system, according to this invention the mixing chamber is connected with a liquid and gas supply system via a two-phase working fluid supply control valve made with a possibility of a preliminary gas flow supply to the mixing chamber, prior to liquid supply into it, when the device starts, and with a possibility of a preliminary cutoff of the liquid flow supplied to the mixing chamber prior to a cutoff of the gas flow fed into it, when the device is turned off.
In the preferred embodiment the nozzle is mounted on the mixing chamber body by a detachable connection. This allows to use changeable nozzles for different operating modes of the device.
It is preferred from the arrangement conditions that a controlled valve be fixed in a common body together with a mixing chamber.
For a comfortable position of the nozzle unit in one""s hand the body is provided with at least one handle. In this case the handle must comprise a trigger mechanism for valve control.
The preferable embodiment of a controlled valve in the form of two closure members on the rod and interacting with the seats located on the sealed chamber walls connected, accordingly, with liquid and gas supply pipes. The valve also includes a rod displacement limiter, a stop rigidly fixed on the rod and a rod displacement control system. One closure member is rigidly fixed on the rod with a possibility of a seat contact in the gas supply chamber, the second stop valve is fixed coaxially on the rod with a possibility of displacement along it and interaction with the stop and the ability of a seat contact in the liquid supply chamber. Between the liquid supply chamber wall and a movable closure member is an elastic component pressing a movable closure member against a corresponding seat. In a normal closed position of the valve a supporting surface of the stop is located with a gap in relation to the opposite supporting surface of the movable closure member.
At least one spring mounted coaxially on the rod can be used as an elastic component.
The gap value is preferably chosen within the range of 0.3 to 1 mm.
The rod displacement control system may include at least one control valve.
It is preferable for the rod displacement control system to be made in the form of a pneumatic system.
Resulting from a device operation control convenience as a control element of a pneumatic system a trigger mechanism is employed placed in the body handle.
The mechanism trigger is hinged to a slide element of the control valve, with the slide element fixed in the valve body with the ability of a limited translation, an elastic component set up between a supporting surface of the slide element and a supporting surface of the device body, e.g., in the form of at least one spring.
A pneumatic system may be provided with a pneumatic cylinder, the piston of which is kinematically connected via a lever mechanism with a controlled valve rod. In this case an elastic component, e.g., in the form of at least one spring resting on the pneumatic cylinder body is fixed in the space above the piston.
The control valve is preferably manufactured with three connections. The first connection takes place with a controlled valve gas chamber. The second connection takes place with a pneumatic cylinder control chamber. The third connection takes place with draining. The slide element has channels linking via the corresponding connection, under the initial position of the trigger mechanism, a pneumatic cylinder control chamber with draining, and while pressing the triggerxe2x80x94a controlled valve gas chamber with a pneumatic cylinder control chamber.
It is also preferred that a liquid and gas supply system contain at least one pressurized gas bottle and one water tank, flexible hoses connecting a cylinder with a liquid chamber of the controlled valve and a cylinder with a gas chamber of the controlled valve and with a gas bottle pressurization cavity, and a gas pressure control valve. The supply system can also include stop valves fixed on liquid and gas supply pipes.
Depending on the size the tank and the bottle can be placed in the back-pack or on a transport means, e.g., a trolley, an automobile or an electromobile.
In utilizing the device as a means of fire extinguishing any liquid applied for this purpose, e.g., water can serve as a working fluid. With the other purpose and a corresponding embodiment of the device the working fluid may be the liquid applied for disaffection, (and/or) deodorization, (and/or) anticeptization of the rooms.
The said technical result is also achieved by the fact that the valve for two-phase working fluid supply comprising two closure members placed on the rod and interacting with the seats located on the sealed chamber walls connected respectively with liquid and gas supply pipes, as well as a rod displacement limiter, and a rod displacement control system according to the invention has a stop rigidly fixed on the rod, one closure member rigidly fixed on the rod with a possibility of a seat contact in a gas supply chamber, the other closure member coaxially mounted on the rod to be able to make a displacement along it, while interacting with a stop and with a possibility of a seat contact in a liquid supply system. Between a liquid supply chamber and a movable closure member is an elastic component in the form of at least, e.g., one spring pressing movable closure member to a respective seat. In a normally closed position of the valve the supporting surface of the stop is located with a gap in relation to the opposite supporting surface of a movable closure component.
The gap value is preferably selected within the range of 0.3 up to 1 mm.
The rod displacement control system structure may include at least one control valve.
It is preferable to carry out a rod displacement control system in the form of a pneumatic system.
A pneumatic system is preferably provided with a pneumatic cylinder, the piston of which is kinematically connected via a lever mechanism with the rod. In this case an elastic component in the form of, e.g., at least one spring resting on the pneumatic cylinder body is mounted in the space above the piston.
A controlled valve is preferred to be manufactured with three connections. The first connection of the valve is with a gas chamber. The second connection communicates with a control pneumatic cylinder chamber. The third connection communicates with draining. The slide component has channels linking via the corresponding connection, under the initial position of a trigger mechanism, the pneumatic cylinder control chamber with draining, and while pressing the triggerxe2x80x94a gas chamber with a pneumatic cylinder control chamber.